1. Coarsely chop mushrooms, rehydrate porcini if using. Put 1/4 cu oil in large soup kettle and saute mushrooms until they release their liquid. Add the garlic and the mint, salt and lots of pepper cook until the ingredients are well blended.
2. Peel, seed and chop the tomatoes. Add the tomatoes and 4 cups of water, cook for about 15 minutes and adjust seasoning.
3. Toast the bread slices, cut the garlic clove and rub the cut side on the toast. Place toast in the bottom of the soup bowl and drizzle with a little oil.
4. Beat the eggs with the cheese in the bottom of a heated soup tureen. Beat a ladleful of hot soup into the egg-cheese mixture and keep adding soup until the mixture is very hot. Pour soup over the toasted bread. Serve with exra grated cheese.